The 1160 m spillway of the Bogus Rim lava dam.

The 1160 m elevation is a plausible call for the 1.8 Ma Bogus Rim lava
dam on the Owyhee River, OR. Consider these points:

1. It does not generate a lake that laps on to western margin of the
subaerial part of the Bogus Rim lava flow upstream.

2. It coincides with the downstream edge of the upstream-most couplet
of Bogus Rim lava remnants on both sides of the gorge below Iron
Point.

3. It is the elevation of the first unequivocal gravel outcrop on the
surface of the Bogus Rim lava flow in the gorge.

Issue: The highest pea gravel clast(s) I can find on the outer edge of
the Bogus Rim flow occur at 1205 m. An exceedingly sparse array of pea
gravel admittedly, but pea gravel nonetheless.

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